Charge management system

ABSTRACT

A charge management system including a power distribution bus circuit for distributing energy from a power source to a load, and an intermediate energy storage circuit operably connected to a power distribution bus circuit for aiding in distribution of energy to the load. A charge management system controller may be configured to control the discharge of energy between the intermediate storage circuit and the power distribution bus circuit during one or more modes. Such a charge management system may enable the power distribution bus circuit to receive energy from the intermediate energy storage circuit before the power bus voltage drops in response to load demand, which may enable the power source to respond to perturbations in the power bus voltage and minimize inrush current from the power source. The system also may be used to soft-start high-power equipment, or absorb energy spikes associated with shut-down.

RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.16/272,457 filed on Feb. 11, 2019, which is a divisional of U.S.application Ser. No. 15/266,531 filed on Sep. 15, 2016, all of which arehereby incorporated herein by reference.

FIELD OF INVENTION

The present invention relates generally to power control circuitry, andmore particularly to a charge management system for improving thedelivery of power from an energy source.

BACKGROUND

Many applications that use electronic devices or electromechanicalequipment, such as electric motors or high pulse current electronicequipment, typically demand high-power output from a power supply. Insuch systems, a circuit is typically designed to deliver power from thepower supply to the equipment load, and capacitors are typically used tolimit voltage drops as the power is supplied. However, during operationor startup of such high-power equipment, the load may change, sometimesrapidly, thereby demanding a large amount of current to be delivered tothe load. In these situations, the inrush current demanded from thepower supply can be relatively high, which may result in damage to thecircuit, the electromechanical equipment, and/or the power supply. Suchhigh inrush current also may generate electromagnetic interference,which may cause problems with the performance of the electromechanicalequipment.

SUMMARY OF INVENTION

The power delivery circuits of the type described above typicallyattempt to address such problems of power disturbance by eitherincreasing the amount of capacitance in the circuit, which may be heavyand bulky, or by the use of control circuitry that reduces theperformance of the equipment during the startup period.

The present disclosure provides, inter alia, a charge management systemthat enables sufficient energy to be distributed from the power supplyto the load, while minimizing power disturbance and peak current drawson the power supply. More particularly, the charge management system mayinclude an intermediate energy storage circuit that is configured tooperate as a bridge for aiding in the distribution of energy during theoperation of such high-power delivery circuits.

For example, the charge management system may be configured such thatthe intermediate energy storage circuit stores energy over a relativelylong period of time, which can then be discharged into a powerdistribution bus circuit when desired.

The charge management system may also include a charge managementcontroller that may be configured to control the discharge of energyfrom the intermediate storage circuit to the power distribution buscircuit by measuring current out of the power bus circuit over a gatedperiod of time.

The intermediate energy storage circuit may include a discharge switchoperably coupled to the charge management controller for controlling theamount of charge that is distributed from the intermediate energystorage circuit to the power bus circuit.

Such a charge management system may enable the power distribution buscircuit to receive energy from the intermediate energy storage circuitbefore the power bus voltage drops in response to load demand. In thismanner, the charge management system may enable the primary power sourceto respond to perturbations in the power bus voltage, which can minimizeinrush current from the primary power source.

For example, when load current demand is increased, the chargemanagement system may enable an instantaneous transfer of energy fromthe intermediate energy storage circuit to the power distribution buscircuit, such that output voltage is increased and the undershoot ofcurrent being sourced from the power supply is reduced. For alternatingcurrent systems that have a boost topology power factor correction, theeffect of right hand plane zeroes may thereby be reduced.

In addition, during operation of devices or equipment using the chargemanagement system, the energy stored by the intermediate energy storagecircuit may be sufficient to allow such equipment to smoothly ramp up tosteady state operation without having excessively high load applied tothe output of the power bus circuit. This may be done without anisolation transformer which is usually used for this purpose.

Such a charge management system may also enable force power sharingbetween multiple sources of energy storage while minimizing oreliminating destabilization of the power distribution bus.

The charge management system may also enable the storage of regenerativeenergy into the intermediate energy storage circuit from the powerdistribution bus circuit when the voltage across the power distributionbus circuit is beyond a predetermined level.

The intermediate energy storage circuit may include a capture chargeswitch operably coupled to the charge management controller forcontrolling the amount of charge that is distributed from the powerdistribution bus circuit to the intermediate energy storage circuit.

The intermediate energy storage circuit also may be utilized tosoft-start devices or equipment, particularly equipment with largeamounts of capacitance across their line input. This may be accomplishedwithout the need for dissipative resistors across input relays of thecharge management system.

The charge management system also may be used to absorb energy spikesassociated with the shut-down of such high-power equipment.

According to one aspect of the invention, a method of operating a chargemanagement system for distributing power from a power source to a load,the charge management system including a power distribution bus circuitoperably connected to the power source and the load, and an intermediateenergy storage circuit operably connected to the power distribution buscircuit, the method including: (i) charging at least one energy storagecapacitor in the intermediate energy storage circuit; (ii) activating adischarge switch to operably connect the at least one energy storagecapacitor to at least one power bus capacitor in the power distributionbus circuit, thereby discharging at least some energy stored in theenergy storage capacitor to the at least one power bus capacitor; (iii)deactivating the discharge switch to operably disconnect the at leastone energy storage capacitor from the at least one power bus capacitor;and (iv) determining whether voltage across the at least one power buscapacitor is within a predetermined range; wherein, when voltage acrossthe at least one power bus capacitor is not within the predeterminedrange during the determining, then repeating steps (i) through (iv); andwherein, when voltage across the at least one power bus capacitor iswithin the predetermined range during the determining, then operablyconnecting the power source to the load.

According to another aspect of the invention, a method of operating acharge management system for distributing power from a power source to aload, the charge management system including a power distribution buscircuit operably connected to the power source and the load, and anintermediate energy storage circuit operably connected to the powerdistribution bus circuit, the method including: (i) operably connectingthe power source to the load; (ii) charging at least one energy storagecapacitor in the intermediate energy storage circuit; (iii) determiningload current demand, and based upon a determination that the loaddemands current that meets or exceeds a predetermined level, activatinga discharge switch to operably connect the at least one energy storagecapacitor in the intermediate energy storage circuit to at least onepower bus capacitor in the power distribution bus circuit, therebydischarging at least some energy stored in the energy storage capacitorand at least some energy stored in the power bus capacitor to the load;(iv) deactivating the discharge switch to operably disconnect the atleast one energy storage capacitor from the at least one power buscapacitor; and (v) repeating steps (ii) through (iv).

According to another aspect of the invention, a method of operating acharge management system for distributing power from a power source to aload, the charge management system including a power distribution buscircuit operably connected to the power source and the load, and anintermediate energy storage circuit operably connected to the powerdistribution bus circuit, the method including: (i) determining voltageacross at least one a power bus capacitor in the power distribution buscircuit, and based upon a determination that the voltage across the atleast one power bus capacitor is greater than a predetermined level,activating a capture charge switch to operably connect the at least onepower bus capacitor to at least one energy storage capacitor in theintermediate energy storage circuit, thereby discharging at least someenergy stored in the at least one power bus capacitor to the at leastone energy storage capacitor; (ii) deactivating the capture chargeswitch to operably disconnect the at least one power bus capacitor fromthe at least one energy storage capacitor; (iii) further charging the atleast one energy storage capacitor in the intermediate energy storagecircuit based upon a determination that the voltage across the at leastone energy storage capacitor is below a predetermined level; (iii)determining load current demand, and based upon a determination that theload demands current that meets or exceeds a predetermined level,activating a discharge switch to operably connect the at least oneenergy storage capacitor to the at least one power bus capacitor,thereby discharging at least some energy stored in the energy storagecapacitor and at least some energy stored in the power bus capacitor tothe load; and (iv) deactivating the discharge switch to operablydisconnect the at least one energy storage capacitor from the at leastone power bus capacitor.

According to another aspect of the invention, a charge management systemfor distributing power from a power source to a load via a powerdistribution bus circuit having at least one power bus capacitor, thecharge management system includes: an intermediate energy storagecircuit operably connected to the power distribution bus circuit, theintermediate energy storage circuit having at least one energy storagecapacitor, and at least one discharge switch configured to operablyconnect or disconnect the at least one energy storage capacitor to orfrom the at least one power bus capacitor; and a system controlleroperably connected to the power bus distribution circuit and theintermediate energy storage circuit.

In a start-up mode, the system controller may be configured to: (i)activate an energy storage capacitor charge switch to operably connectthe at least one energy storage capacitor to at least one energy source,thereby enabling charging of the at least one energy storage capacitor;(ii) activate a discharge switch to operably connect the at least oneenergy storage capacitor to the at least one power bus capacitor,thereby enabling discharging of at least some energy stored in theenergy storage capacitor to the at least one power bus capacitor; (iii)deactivate the discharge switch to operably disconnect the at least oneenergy storage capacitor from the at least one power bus capacitor; and(iv) determine whether the voltage across the at least one power buscapacitor is within a predetermined range, such that, based upon adetermination that the voltage across the at least one power buscapacitor is not within the predetermined range, the controller isconfigured to repeat steps (i) through (iv), and based upon adetermination that the voltage across the at least one power buscapacitor is within the predetermined range during the determining, thecontroller is configured to activate a power relay switch to operablyconnect the power source to the load.

In an operational mode, the system controller may be configured to: (i)operably connect the power source to the load; (ii) determine whetherthe voltage across the at least one energy storage capacitor is at orabove a predetermined level, and based upon a determination that thevoltage across the energy storage capacitor is below the predeterminedlevel, the controller is configured to activate the energy storagecapacitor charge switch to operably connect the at least one energystorage capacitor to the at least one energy source, thereby enablingcharging of the at least one energy storage capacitor; (iii) determineload current demand, and based upon a determination that the loaddemands current that meets or exceeds a predetermined level, activatingthe discharge switch to operably connect the at least one energy storagecapacitor to the at least one power bus capacitor, thereby enablingdischarging of at least some energy stored in the energy storagecapacitor and at least some energy stored in the power bus capacitor tothe load; and (iv) deactivating the discharge switch to operablydisconnect the at least one energy storage capacitor from the at leastone power bus capacitor.

In a regenerative mode, the controller may be configured to determinevoltage across the at least one a power bus capacitor, and based upon adetermination that the voltage across the at least one power buscapacitor is greater than a predetermined level, the controller isconfigured to activate a capture charge switch to operably connect theat least one power bus capacitor to the at least one energy storagecapacitor, thereby enabling discharging of at least some energy storedin the at least one power bus capacitor to the at least one energystorage capacitor.

The following description and the annexed drawings set forth certainillustrative embodiments of the invention. These embodiments areindicative, however, of but a few of the various ways in which theprinciples of the invention may be employed. Other objects, advantagesand novel features according to aspects of the invention will becomeapparent from the following detailed description when considered inconjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The annexed drawings, which are not necessarily to scale, show variousaspects of the invention.

FIG. 1 is a schematic block diagram of an exemplary charge managementsystem according to an embodiment of the invention.

FIG. 2 is a flow chart illustrating an exemplary start-up mode using thecharge management system in FIG. 1.

FIG. 3A is an x-y plot diagram illustrating an exemplary simulationaccording to a portion of the start-up mode in FIG. 2. FIG. 3B is aclose-up view of FIG. 3A.

FIG. 4A is an x-y plot diagram illustrating a simulation of a start-upmode according to a system that does not use the charge managementsystem in FIG. 1.

FIG. 4B is an x-y plot diagram illustrating an exemplary simulation of astart-up mode using the charge management system in FIG. 1.

FIG. 5 is a flow chart illustrating an exemplary operational mode usingthe charge management system in FIG. 1.

FIG. 6A is an x-y plot diagram illustrating a simulation of anoperational mode according to a system that does not use the chargemanagement system in FIG. 1.

FIG. 6B is an x-y plot diagram illustrating an exemplary simulation ofan operational mode using the charge management system in FIG. 1.

FIG. 7 is a flow chart illustrating an exemplary regenerative mode usingthe charge management system in FIG. 1.

FIG. 8 is an x-y plot diagram illustrating an exemplary simulation of aregenerative over-volt protection mode during a start-up period usingthe charge management system in FIG. 1.

FIG. 9 is a flow chart illustrating an exemplary shut-down mode usingthe charge management system in FIG. 1.

FIGS. 10A and 10B are x-y plot diagrams illustrating a simulation of ashut-down mode according to a system that does not use the chargemanagement system in FIG. 1.

FIGS. 11A and 11B are x-y plot diagrams illustrating an exemplarysimulation of a shut-down mode using the charge management system inFIG. 1.

FIG. 12 is an exemplary circuit diagram of an exemplary chargemanagement system according to an embodiment of the invention.

DETAILED DESCRIPTION

The principles of the present invention have particular application forhigh-power devices or equipment, such as electric motors, radars,Lidars, electronic warfare systems, pulsed radio frequency high-powerdirected energy weapons, or the like, and will thus be described belowchiefly in this context. It is also understood, however, that principlesof this invention may be applicable to other systems or applicationswhere it is desirable to provide a charge management system that enablessufficient energy to be distributed from a power supply to a load whileminimizing power disturbance and peak current draws on the power supply.

Turning to FIG. 1, a schematic block diagram of an exemplary chargemanagement system 10 is shown. The charge management system 10 includesa power distribution bus circuit 12, an intermediate energy storagecircuit 14, and a charge management system controller 16 (also referredto as the system controller 16).

The power distribution bus circuit 12 may be operably connected to aprimary power source V1 and a load 20. The load 20 may include one ormore devices or equipment, such as electromechanical equipment, thatdemands power from the power source V1. Such electromechanical equipmentmay include alternating current (AC) or direct current (DC) electricmotors, such as regenerative electric motor drives, that may be used forvehicles, such as a serial-hybrid or a parallel-hybrid vehicle; or theelectromechanical equipment may include high-power electronic equipment,such as radars, Lidars, electronic warfare (EW) systems, pulsed radiofrequency (RF) high-power directed energy weapons, or the like. Theprimary power source V1 (also referred to as the power source or powersupply) may be an AC power source or a DC power source. For example, theAC power source may include an AC generator having a power factorcorrection (PFC) circuit, such as a three-phase rectifier assembly, forconverting the AC power to DC. The DC power source may include, forexample, battery packs, solar arrays, or a fuel cell, such as a hydrogenpowered fuel cell. In exemplary non-limiting embodiments, the primarypower source V1 may be a voltage source having 115Vac, 270Vdc, 400Vdc,or 540Vdc output voltage, or any other arbitrary voltage with anarbitrary frequency. It is understood that the foregoing examples ofloads and/or power sources are for illustration and not limitation, andany suitable device operable by AC or DC power may be selected dependingon the system requirements as understood by those having skill in theart.

The power distribution bus circuit 12 may include one or more primarypower relay switches S1, S2 and at least one power bus capacitor C1. Theprimary power relay switches S1, S2 may be configured to operablyconnect the power source V1 to the load 20. The one or more primarypower relay switches S1, S2 may include mechanical or solid stateswitches, or may include any other suitable device for interrupting theflow of electricity in the circuit. The at least one power bus capacitorC1 may be configured to store energy across the power distribution buscircuit 12. The power bus capacitor C1 may include an electrolyticcapacitor, such as aluminum electrolytic capacitor; or a supercapacitor, such as a high-capacity electrochemical capacitor; or mayinclude any other capacitor having suitable capacitance for storingenergy or charge in the circuit.

The intermediate energy storage circuit 14 may be operably connected tothe power distribution bus circuit 12. The intermediate energy storagecircuit 14 also may be operably connected to at least one energy sourceV2, which may include an AC power source or a DC power source. In someembodiments, the at least one energy source V2 may be substantiallysimilar to or the same as the primary power source V1. For example,where the energy source V2 and the primary power source V1 are the sameor similar, the at least one energy source V2 and the primary powersource V1 may be operably coupled together to share the same power path,or may be integral with each other. In other embodiments, the at leastone energy source V2 may be different from the primary power source V1.For example, where the at least one energy source V2 and the primarypower source V1 are different, the at least one energy source V2 and theprimary power source V1 may be operably coupled together to havedifferent power paths, or may be integral with each other and havedifferent power stages, or the at least one energy source V2 may be aseparate standalone power source from the primary power source V1. Insome embodiments, the at least one energy source V2 may be a pluralityof energy sources operably coupled together in series or parallel. Inexemplary embodiments the at least one energy source V2 may be AC,battery storage, or may be a fuel cell that generates DC, such as ahydrogen fuel cell, or, solar arrays, for example. In exemplaryembodiments the energy source V2 may be a voltage source having arelatively low wattage. For example, in some embodiments, the energysource V2 may have a voltage of about 400Vdc and a wattage of about 25W. However, it is understood that the foregoing examples of the energysource are for illustration and not limitation, and any suitable energysource operable by AC or DC power may be selected depending on thesystem requirements as understood by those having skill in the art.

The intermediate energy storage circuit 14 may include at least onecapacitor C5 for storing energy in the circuit 14. For example, as shownin the illustrated embodiment, the at least one capacitor C5 may includea first energy storage capacitor C2, a second energy storage capacitorC3, and a third energy storage capacitor C4. As shown, the secondcapacitor C3 and the third capacitor C4 may be operably connected inseries with each other across the intermediate energy storage circuit14, and the first energy storage capacitor C2 may be operably connectedin parallel to the second capacitor C3 and the third capacitor C4. It isunderstood that the respective energy storage capacitors C2, C3, and/orC4 may be substantially similar to each other, or the respectivecapacitors C2, C3, and/or C4 may be different from each other. Theenergy storage capacitors C2, C3, and/or C4 may include an electrolyticcapacitor, such as aluminum electrolytic capacitor; or a supercapacitor, such as a high-capacity electrochemical capacitor; or mayinclude any other capacitor having suitable capacitance for storingenergy or charge in the circuit. In exemplary embodiments, therespective capacitors C2, C3, and/or C4 may have about the samecapacitance or energy storage capacity as each other, which may be lessthan the capacitance or energy storage capacity of the power buscapacitor C1.

The intermediate energy storage circuit 14 may include at least oneswitch for operably connecting and/or disconnecting the intermediateenergy storage circuit to or from the power distribution bus circuit 12and/or the energy source V2. For example, as shown in the illustratedembodiment, the intermediate energy storage circuit 14 may include atleast one energy storage capacitor charge switch S3 for operablyconnecting or disconnecting the at least one energy storage capacitor C5to or from the energy source V2. In exemplary embodiments, theintermediate energy storage circuit 14 is configured such that, when theenergy storage capacitor charge switch S3 is activated, the energysource V2 is able to charge the at least one energy storage capacitorC5, including one or more of the respective capacitors C2, C3, and/orC4.

The intermediate energy storage circuit 14 also may include at least onedischarge switch S4 for operably connecting or disconnecting the atleast one energy storage capacitor C5 to or from the power distributionbus circuit 12. As shown, the discharge switch S4 (also referred to asan energy storage capacitor discharge switch) may be configured suchthat, when activated, causes at least some energy from the at least oneenergy storage capacitor C5, including one or more of the energy storagecapacitors C2, C3 and/or C4, to be discharged to the power bus capacitorC1 and/or to the load 20.

The intermediate energy storage circuit 14 may further include at leastone energy capture charge switch S5 for operably connecting ordisconnecting the power bus capacitor C1 to the at least one energystorage capacitor C5. More particularly, the capture charge switch S5may be configured such that, when activated, causes at least some energyin the power bus capacitor C1 to be discharged to the at least oneenergy storage capacitor C5, including one or more of the first energystorage capacitor C5, and the energy storage capacitors C3 and C4 (alsoreferred to as energy capture capacitors). It is understood that therespective switches S3, S4 and/or S5 may include mechanical or solidstate switches, including field effect transistors (FETs), or the like;or may include any other suitable device for interrupting the flow ofcurrent in the circuit.

The system controller 16 may be operably connected to the one or moreswitches in the power distribution bus circuit 12, including the powerrelay switches S1 and S2, and also may be operably connected to the oneor more switches in the intermediate energy storage circuit 14,including the energy storage capacitor charge switch S3, the dischargeswitch S4, and the capture charge switch S5. As will be described infurther detail below, the system controller 16 may be configured tooperate the exemplary charge management system 10 by activating ordeactivating the respective switches based upon a determination of oneor more conditions associated with the respective circuits 12 and 14,the energy source V2, the primary power source V1, and/or the load 20,among other considerations. It is understood that the system controller16 may encompass all apparatus, devices, and/or machines for processingdata. For example, the system controller 16 may include a digital signalprocessor (DSP), an application specific integrated circuit (ASIC), afield-programmable gate array (FPGA) integrated circuit, an analogcontroller, discrete control circuitry, or any other suitable device forcontrolling operation of the charge management system 10.

Turning to FIG. 2, a flow chart illustrating an exemplary method 100 ofoperating the charge management system 10 during a start-up mode isshown. The exemplary process may begin at step 105 where the chargemanagement system is activated and enters the start-up mode. At step110, the system controller 16 may deactivate or open all switches in therespective circuits 12 and 14, including switches S1, S2, S3, S4 and S5.Once it is determined that all of the switches have been deactivated,the process may proceed to step 115 where power may be applied to theenergy source V2. At step 120, the energy storage capacitor chargeswitch S3 may be activated or turned-on to operably connect the energysource V2 to the at least one energy storage capacitor C5. Thereafter,at step 125, the at least one energy storage capacitor C5, including oneor more of the energy storage capacitors C2, C3 and/or C4, may becharged by the energy source V2 to a predetermined energy level orpredetermined energy range. In exemplary embodiments, the typical stepvoltage defining the predetermined range will be approximately 1-2% ofthe voltage across the power bus capacitor C1. By way of a non-limitingexample, if the power bus capacitor C1 is to be charged to 270Vdc, thetypical step voltage defining the predetermined range will beapproximately 1-2% of 270Vdc, or 5-10Vdc±2Vdc. In exemplary embodiments,the energy source V2 is a voltage source that charges the at least oneenergy storage capacitor C5 to a voltage determined by the voltagesource, where the rate of such charge may be arbitrary. This may allowfor the voltage source to be a small wattage power supply, such as about10 W, for example. It is noted at this point during the operation, whenthe energy storage capacitor charge switch S3 is activated and theenergy capture charge switch S5 is deactivated, the second capacitor C3and the third capacitor C4 may be operably connected in series with eachother across the intermediate energy storage circuit 14, and the firstenergy storage capacitor C2 may be operably connected in parallel to thesecond capacitor C3 and the third capacitor C4. It is also noted that atthis point during the operation, the discharge switch S4 is deactivatedto operably disconnect the at least one energy storage capacitor C5 fromthe power bus circuit 12. In this manner, as the load 20 is usuallyisolated from the power source V1, such as via a transformer, the load20 is also disconnected from the at least energy storage capacitor C5.

After it has been determined that the at least one energy storagecapacitor C5 has been charged to the predetermined level, the start-upoperation may proceed to step 130 where the energy storage capacitorcharge switch S3 may be deactivated or turned-off to operably disconnectthe at least one energy storage capacitor C5 from the energy source V2.At step 135, the discharge switch S4 is activated to operably connectthe at least one energy storage capacitor C5 to the at least one powerbus capacitor C1 in the power distribution bus circuit 12. Once thedischarge switch S4 has been activated in this manner, at least some ofthe energy stored in the at least one energy storage capacitor C5 may beinstantaneously discharged to the power bus capacitor C1 and stored. Inexemplary embodiments, the discharge of energy from the at least oneenergy storage capacitor C5 includes discharge of the energy stored inthe energy storage capacitor C2 that is in parallel with the combinationof the energy storage capacitors C3 and C4, which are connected inseries with each other.

At step 140, the system controller 16 may determine whether thedischarging of the at least one energy storage capacitor C5 to the atleast one power bus capacitor C1 is complete (e.g., whether voltageacross the at least one energy storage capacitor C5 and the voltageacross the power bus capacitor C1 are within a predetermined range. Inexemplary embodiments, the typical charge termination voltage definingthe predetermined range will be approximately 90% of the voltage acrossthe power bus capacitor C1. By way of a non-limiting example, if thepower bus capacitor C1 is to be charged to 270Vdc, the typical chargetermination voltage defining the predetermined range will beapproximately 90% of 270Vdc, or 250Vdc. If it is determined that thedischarging is not complete, then the operation may wait and continuedischarging C5 and charging C1. Once the discharging is complete (e.g.,voltage across the respective capacitors C5, C1 is within thepredetermined range), then the start-up operation may proceed to step145 whereby the discharge switch S4 is deactivated to operablydisconnect the at least one energy storage capacitor C5 from the atleast one power bus capacitor C1. Thereafter, at step 150, the systemcontroller 16 determines whether the voltage across the at least onepower bus capacitor C1 is within a specified range, such as at thecharge termination voltage defined above. If it is determined that thepower bus capacitor C1 has not been charged to within the specifiedrange, then the process repeats by proceeding to step 120. When it isdetermined that the power bus capacitor C1 has been charged to withinthe specified range, then the process may proceed to step 155 where theprimary power relay switches S1, S2 are activated to operably connectthe power source V1 to the load 20.

Referring to FIG. 3A, an x-y plot diagram illustrating a portion of thestart-up operation 100 is shown. In the illustrated diagram, the voltageacross the at least one energy storage capacitor C5 (in volts) isplotted on the y-axis in the top portion 162 of the graph, and thevoltage across the at least one power bus capacitor C1 (in volts) isplotted on the y-axis in the bottom portion 164 of the graph. Thevoltage of C5 (162) and the voltage of C1 (164) are plotted over thesame time scale (x-axis, in seconds) during the sequence of charging theat least one energy storage capacitor C5 (e.g., via steps 120 through130 discussed above with reference to FIG. 2), and then discharging thatenergy to the power bus capacitor C1 (e.g., via steps 135 through 145discussed above), and then repeating this sequence (e.g., via step 150and back to step 120, as discussed above).

Referring to FIG. 3B, a close-up view of a portion of FIG. 3A is shownbetween the times of about 325 milliseconds to about 950 milliseconds.The reference numerals used in FIG. 3B correspond to the respectivesteps in the flow chart of FIG. 2 to illustrate the exemplary start-upmode of operation 100 for the charge management system 10. For example,as shown in FIG. 3B, when the energy storage capacitor charge switch isactivated (step 120′), the at least one energy storage capacitor ischarged by the energy source (step 125′), which is shown as the energystorage capacitor voltage ramps up over the next 50 milliseconds, or so.The energy storage capacitor is charged to a predetermined level orrange, which in the exemplary embodiment is about a 20V increase fromabout 95V to about 105V at this point during the operation. The 20Vincrease is an arbitrary value that was selected in this non-limitingexample so as to demonstrate the operation of the circuitry. The energycapacitor charge switch is then deactivated (step 130′) and soon afterthe energy storage capacitor discharge switch is activated (step 135′),thereby discharging the energy stored in the energy storage capacitor tothe power bus capacitor, which is shown as the instantaneous increase ofthe power bus capacitor voltage to within a predetermined range. In thisnon-limiting example, the predetermined range is defined by the voltageacross the power bus capacitor being about equal with the energy storagecapacitor voltage, or about 20Vdc±2Vdc in the exemplary embodiment.During this time, the system controller may determine whether thevoltage across the power bus capacitor is within the predetermined range(step 140′), and once the voltage across the power bus capacitor reachesthis range, then the discharge switch is deactivated (step 145′). Thesystem controller may then determine whether the voltage across thepower bus capacitor is within a specified range to activate the primarypower switch (step 150′). If the voltage across the power bus capacitorshould still be increased, then the process repeats, which is shown inthe exemplary embodiment as repeating about every 55 milliseconds untilthe power bus capacitor voltage reaches 240V in this example (shown inFIG. 3A). When it is determined that the power bus capacitor voltage iswithin the specified range, such as 240V in this example, the primarypower switch is activated (step 155′).

Referring to FIGS. 4A and 4B, an exemplary simulation of the start-upmode of operation is shown using the exemplary charge management system10 (shown in FIG. 4B) compared with a start-up mode of operation thatdoes not use the charge management system (shown in FIG. 4A). As shownin FIG. 4A, during the start-up of the system that does not use theexemplary charge management system, the peak inrush current when thepower source is operably connected to the load is 450 amperes (shown atreference numeral 165′). In comparison, referring to the top graph 170in FIG. 4B, the repeated step function is shown, which corresponds tothe increase in voltage of the power bus capacitor over time (similarlyto that which is shown in FIG. 3). As shown in the bottom graph 175 ofFIG. 4B, when the power source is connected to the load, the peak inrushcurrent is only 42 amperes (as shown at reference numeral 165″), whichis about a 90% reduction over the system that does not use the chargemanagement system. In the illustrated example, the 42 amperes of inrushcurrent using the exemplary charge management system is only marginallyhigher than the 39 amperes of current drawn from a 10 W power supplyduring full load operation. In addition, the illustrated example showsthat such a charge management system may allow the at least one powerbus capacitor for a 10 W power supply to be charged up by a 25 W energysource to attain normal operating voltage in 5 seconds without the useof dissipative resistors.

Turning to FIG. 5, a flow chart illustrating an exemplary method 200 ofoperating the charge management system 10 during a normal operationalmode is shown. The operation may begin at step 210, where the systemcontroller 16 may enter the operational mode following the start-up modeillustrated in FIG. 2. During the operational mode 200, the primarypower source V1 is activated and is operably connected to the load 20,as shown in steps 212 and 214. It is also noted that when entering theoperational mode at step 210, based upon a determination that the atleast one energy storage capacitor C5 is below a threshold level andneeds charged, the process may optionally also proceed to step 224 wherethe energy storage capacitor charge switch S3 is activated to charge theat least one energy storage capacitor C5, as discussed in further detailbelow.

After the load is applied in step 214, the process may then proceed tostep 216 where the system controller 16 may determine load currentdemand. The operation may then wait until the system controller 16determines that the load 20 demands current that meets or exceeds apredetermined level, whereupon the process may then proceed to step 218.The predetermined level may be selected according to designrequirements, as understood by those having skill in the art. Forexample, in exemplary embodiments, the predetermined level may be about25±2% of maximum pulsed load. At step 218, the energy storage dischargeswitch S4 is activated to operably connect the at least one energystorage capacitor C5 to the at least one power bus capacitor C1, therebydischarging at least some energy stored in the energy storage capacitorC5 and at least some energy stored in the power bus capacitor C1 to theload 20. The charge transfer to the load is given by the equation:Vbus=[V(initial of storage cap)*Capacitance(storage cap C5)+V(initial ofbus cap)*Capacitance(bus cap C1)]/[Capacitance(storage capC5)+Capacitance(bus cap)C1]where:

Vbus is the voltage across the power bus circuit 12,

V(initial of storage cap) is the initial voltage across the at least onestorage capacitor C5,

Capacitance(storage cap) is the capacitance of the at least one storagecapacitor C5 (in combination),

V(initial of bus cap) is the voltage across the at least one power buscapacitor C1, and

Capacitance(bus cap) is the capacitance of the at least one power buscapacitor C1.

In exemplary embodiments, when the discharge switch S4 is activated, theenergy is instantaneously transferred to the load 20 from the power buscapacitor C1 in parallel combination with the at least one energystorage capacitor C5 (including the energy storage capacitor C2 that isin parallel with the combination of the energy storage capacitors C3 andC4, which are connected in series with each other). Advantageously, suchan instantaneous charge transfer of energy to the load 20 increases theoutput voltage of the power distribution bus circuit 12, which mayreduce undershoot associated with right-hand plane zeroes in boosttopology power sources. In other words, right-hand plane zeroes areoften caused by the transfer function:Vout=Vin*(1/1−DC)where:

Vout is the voltage out of the power bus circuit 12 to the load 20,

Vin is the voltage into the power bus circuit 12 from the power sourceV1, and

DC is the current, such as direct current, demanded by the load.

Accordingly, increased current demanded by the load may cause thecurrent, or DC, to increase because Vout decreases. However, by usingthe exemplary charge management system and instantaneously transferringcharge in the manner described above, instead of DC decreasing, the DCincreases thereby forcing the voltage going to an error amplifier toalso increase. The result is that Vout increases and the undershootassociated with the right-hand plane zeroes is reduced.

After the discharge switch S4 has been activated at step 218 and duringthe discharge of the respective capacitors C1 and C5 (including one ormore of C2, C3 and C4), the system controller 16 may determine at step220 whether the discharging is complete (e.g., whether voltage acrossthe at least one energy storage capacitor C5 and the voltage across thepower bus capacitor C1 are within a predetermined range, such as about±10% of each other. If it is determined that the discharging is notcomplete, then the operation may wait and continue the discharging. Oncethe discharging is complete (e.g., voltage across the respectivecapacitors C5, C1 is within ±10% of each other), then the operation mayproceed to step 222 where the discharge switch S4 is deactivated tooperably disconnect the at least one energy storage capacitor C5 fromthe at least one power bus capacitor C1.

After the discharge switch S4 has been deactivated at step 222, theoperation may then proceed to repeat steps 216 through 222. The processmay proceed in this manner based on a determination that the at leastenergy storage capacitor C5 has sufficient charge to accommodateincreased load current demand, as discussed above. On the other hand,when it is determined that the at least one energy storage capacitor C5is below a threshold energy level and may require additional charge,then the process may proceed from step 222 to step 224. At step 224, theenergy storage capacitor charge switch S3 may be activated to operablyconnect the energy source V2 to the at least one energy storagecapacitor C5. Thereafter, at step 226, the at least one energy storagecapacitor C5 may be charged by the energy source V2 to a predeterminedenergy level or predetermined energy range, which may be determined bythe system controller 16 at step 228. By way of a non-limiting example,for a 270Vdc power bus voltage C1, the voltage across the at least oneenergy storage capacitor C5 may be about 400Vdc±10Vdc. After it has beendetermined that the at least one energy storage capacitor C5 has beencharged to the predetermined level, the operation may proceed to step230 where the energy storage capacitor charge switch S3 is deactivatedto operably disconnect the at least one energy storage capacitor C5 fromthe energy source V2. The process then waits at step 232 until there isa discharge command from the system controller 16. As shown, thedischarge command may be based upon a determination to activate thedischarge switch S3 at step 216, whereupon the process proceeds to enterthe loop at step 218.

Referring to FIGS. 6A and 6B, an exemplary simulation of the operationalmode 200 is shown using the exemplary charge management system 10 (shownin FIG. 6B) compared to an operational mode that does not use the chargemanagement system (shown in FIG. 6A). As shown in FIG. 6A, duringoperation of the system that does not use the exemplary chargemanagement system, the baseline current demanded by the load is lessthan 5 amperes (shown at reference numeral 265′), and when the loaddemands increased current, the peak inrush current to the load increasesto about 95 amperes (shown at reference numeral 270′). In comparison,referring to FIG. 6B, during operation of the exemplary chargemanagement system 10, the baseline current demanded by the load is alsoless than 5 amperes (shown at reference numeral 265″), however when theload demands increased current and it is determined to activate thedischarge switch S4 to discharge the energy from the at least one energystorage capacitor C5, the peak inrush current to the load only increasesto about 42 amperes (shown at reference numeral 270″). As discussedabove with respect to the start-up mode of operation, the 42 amperes ofinrush current using the exemplary charge management system during theoperational mode is only marginally higher than the 39 amperes ofcurrent drawn from a 10 W power supply during full-load operation. Inthis manner, the charge management system may reduce the load appliedinrush by about 50%, and using a 25-watt energy source, this 50%reduction can be realized every 5 seconds, for example.

Turning to FIG. 7, a flow chart illustrating an exemplary method 300 ofoperating the charge management system 10 during a regenerative mode isshown. The operation may begin at step 310 where the system controller16 may enter into a power bus monitor mode during the normal operationalmode shown in FIG. 5. As shown at step 310 in FIG. 5, the power busmonitor mode may be constantly operating while the load 20 is applied.As shown in FIG. 7, after entering the power bus monitor mode at step310, the process may proceed to step 315 where the system controller 16may determine voltage across the at least one power bus capacitor C1 inthe power distribution bus circuit 12. If the system controller 16determines that the power bus capacitor C1 has an energy level that isbelow a threshold energy level or range, the controller may continue tomonitor the power bus capacitor C1 and wait. When the system controller16 determines that the voltage across the at least one power buscapacitor C1 is greater than a predetermined level or range, then theprocess may proceed to step 320 and/or step 325.

At step 320, the system controller 16 may optionally deactivate theenergy storage charge switch S3 and also may deactivate the dischargeswitch S4. At step 325, the energy capture switch S5 may be activated tooperably connect the at least one power bus capacitor C1 to the at leastone energy storage capacitor C5, thereby discharging at least someenergy stored in the at least one power bus capacitor C1 to the at leastone energy storage capacitor C5 (including one or more of the capacitorsC2, C3, and/or C4). In exemplary embodiments, when the energy storagecapacitor charge switch S3 is deactivated and the energy capture chargeswitch S5 is activated, the second energy storage capacitor C3 and thefirst energy storage capacitor C2 may be operably connected in serieswith each other, and the third energy storage capacitor C4 may beoperably connected in parallel to both the second capacitor C3 and thefirst capacitor C2. In this manner, when the capture charge switch S5 isactivated, the energy from the power bus capacitor C1 may be transferredto the third capacitor C4, which is in parallel with C1 and C2, whichare in series with each other.

After the capture charge switch S5 has been activated at step 325 andduring the discharge of energy from the power bus capacitor C1 to the atleast one energy storage capacitor C5, the system controller 16 maydetermine at step 330 whether the discharging is complete (e.g., voltageacross the at least one energy storage capacitor C5 and the voltageacross the power bus capacitor C1 are within a predetermined range, suchas about ±5% of the maximum allowable voltage of the power bus circuit12. For example, in exemplary embodiments, a 270Vdc may be allowed to goto 320Vdc, which would allow for a voltage spike of 270Vdc±13Vdc. Thiswould be well within the allowable voltage of a 400V-rated capacitor. Ifit is determined that the discharging is not complete, then theoperation may wait and continue discharging. Once the discharging iscomplete (e.g., when voltage across C5 and C1 is within thepredetermined range), then the operation may proceed to step 335 wherethe capture charge switch S5 is deactivated to operably disconnect theat least one power bus capacitor C1 from the at least one energy storagecapacitor C5.

After the capture charge switch S5 has been deactivated at step 335, theoperation may optionally proceed to step 340 and then to step 350 toenter a capacitor charge mode as shown in FIG. 5. The process mayproceed in this manner based on a determination that the at least oneenergy storage capacitor C5 is below a threshold energy level and mayrequire additional charge. If it is determined that the at least oneenergy storage capacitor C5 should be charged, the energy storagecapacitor charge switch S3 may be activated at step 340 to operablyconnect the energy source V2 to the at least one energy storagecapacitor C5, thereby charging the at least one energy storage capacitorC5 as shown at step 226 of FIG. 5. Energy stored in the energy storagecapacitor C5 may later be used in the start-up or operational modesdescribed above. This way energy is conserved instead of being wasted asin prior art circuit designs, thus improving efficiency.

Turning to FIG. 8, an exemplary simulation of a regenerative over-voltprotection mode during a portion of an exemplary start-up period usingthe charge management system 10 is shown. In the illustrated example, aclose-up view of a time period (x-axis) between about 8.89 millisecondsand about 8.95 milliseconds during the start-up mode is shown. A topportion 362 of the x-y plot in FIG. 8 depicts voltage of the firstenergy storage capacitor C2 (y-axis, in volts), a middle portion 364 ofthe x-y plot depicts voltage across the power bus capacitor C1 (y-axis,in volts), and a bottom portion 366 of the x-y plot depicts voltageacross the third energy storage capacitor C4 (y-axis, in volts). Thevoltage of C2 (362), the voltage of C1 (364), and the voltage of C4(366) are plotted over the same time scale (x-axis, in milliseconds)during the illustrated sequence.

As shown in FIG. 8, during an initial period between about 8.895milliseconds and about 8.908 milliseconds, the voltage of the thirdenergy storage capacitor C4 is constant at about 106Vdc. During thisinitial period, the energy capture charge switch S5 is deactivated andthe energy discharge switch S4 is also deactivated. At about 8.908milliseconds, the energy capture charge switch S5 is activated (shown atreference numeral 370), whereupon the energy storage capacitor C4charges from about 106Vdc to about 256Vdc almost instantaneously (shownat reference numeral 372). During this time when the capture chargeswitch S5 is initially activated, the voltage of the power bus capacitorC1 decreases almost instantaneously from about 295Vdc to about 271Vdc(shown at reference numeral 374). The approximately 15 volts ofdifference between the power bus capacitor C1 (at about 271Vdc) and theenergy storage capacitor C4 (at about 256Vdc) is due to the resistancein the capture charge switch S5.

In the illustrated example, the energy storage capacitor charge switchS3 is also activated during the time period when the energy capturecharge switch S5 is activated, and the discharge switch S4 remainsdeactivated. In this configuration, the second energy storage capacitorC3 and the first energy storage capacitor C2 may be operably connectedin series with each other across the intermediate energy storage circuit14, and the third energy storage capacitor C4 may be operably connectedin parallel to the series combination of the second capacitor C3 and thefirst capacitor C2. In this manner, over the time period when S5 isactivated and S3 is activated, the voltage of the energy storagecapacitor C2 increases at a linear rate by the parallel coupling betweenC4 and C2. For example, as shown at reference numeral 376, the voltageof C2 increases by about 1.5Vdc over the time period of about 624nanoseconds when S5 and S3 are activated. It is noted, however, that inexemplary embodiments the energy charge switch S3 may be deactivatedduring the time period when the capture charge switch S5 is activated.In comparison to the illustrated example, this would have resulted inthe voltage of the first energy storage capacitor C2 increasing by about0.3Vdc over the 624 nanosecond time period when S5 were activated.

As shown, after the timed pulse period of about 624 nanoseconds, thecapture charge switch S5 is deactivated (shown at reference numeral378). In the illustrated example, when the capture charge switch S5 isdeactivated, the voltage across the energy storage capacitor C4 is about7Vdc higher than it was before the pulsed charge event due to thetransfer of at least some energy from the power bus capacitor C1. Inaddition, the voltage across the energy storage capacitor C1 is about1.5Vdc higher than it was before the pulsed charge event. In thismanner, at least some charge has been transferred from the power buscapacitor C1 to the at least one energy storage capacitor C5 during theexemplary start-up period. As shown, the process may repeat after apredetermined period of time, for example at about 8.942 milliseconds inthe illustrated example. It is understood that the foregoing example isfor illustration, and not limitation, and various other voltage valuesand time values could be used, as understood by those having skill inthe art. It is also understood that such an exemplary regenerativeover-volt protection mode may be used during the operational modedescribed above.

Turning to FIG. 9, a flow chart illustrating an exemplary method 400 ofoperating the charge management system 10 during a shutdown mode isshown. The operation may begin at step 410 where the system controller16 enters a shutdown monitor mode during the normal operational modeshown in FIG. 5. As shown at step 410 in FIG. 5, the shutdown monitormode may be constantly operating while the load 20 is applied. As shownin FIG. 9, after entering the shutdown monitor mode at step 410, theprocess may proceed to step 415 where the system controller 16 maydetermine whether a shutdown command signal has been received. If thesystem controller 16 determines that such a shutdown command signal hasnot been received, the controller may continue to monitor the system andwait. When the system controller 16 determines a shutdown command signalhas been received, then the load 20 may be deactivated and may beoperably disconnected from the power source V1 by deactivating theprimary power relay switches S1, S2. The process may then proceed tostep 420, step 425 and/or step 430. As shown, at step 420, the energystorage capacitor charge switch S3 is deactivated to operably disconnectthe at least one energy storage capacitor C5 from the energy source V2.At step 425, the capture charge switch S5 is deactivated to operablydisconnect the power bus capacitor C1 from the at least one energystorage capacitor C5, so as to impede charging in the intermediateenergy storage circuit 12. At step 430, the energy storage capacitordischarge switch S4 is activated to operably connect the at least oneenergy storage capacitor C5 to the power bus capacitor C1, therebydischarging the energy stored in the respective capacitors C2, C3, C4.As shown at step 435, the energy stored in the at least one energystorage capacitor C5 and the energy stored in the power bus capacitor C1may be discharged to an optional resistor discharge circuit (not shown).The process may then end at the off-state shown at step 450.

In exemplary embodiments, the shut-down mode may also include aregenerative over-volt protection mode to discharge and store the excessenergy in the power bus circuit 12 caused by deactivation of the load20. For example, when the system controller 16 determines that the load20 has been deactivated and/or that the voltage across the power buscapacitor C1 is over a predetermined level, the energy storage dischargeswitch S3 may be deactivated and the capture charge switch S5 may beactivated. The excess energy from the power bus capacitor C1 may then bedischarged to the at least one energy storage capacitor C5, and moreparticularly the energy capture capacitors C3 and C4, for storage ofsuch energy.

Referring to FIGS. 10A, 10B, 11A, and 11B, an exemplary simulation ofsuch regenerative over-volt protection during a shut-down mode is shownusing the exemplary charge management system 10 (shown in FIGS. 11A and11B) compared to such a mode that does not use the charge managementsystem (shown in FIGS. 10A and 10B). In the illustrated examples ofFIGS. 10A, 10B, 11A, and 11B, the primary power source (e.g., V1) is270Vdc, and the energy source (e.g., V2) is a voltage source having400Vdc. The load (e.g., 20) may be operably disconnected from the powerdistribution bus circuit (e.g., 12) via field effect transistors (FETs)or the like.

In the illustrated example, FIG. 10A depicts current (in amperes)through the load (c.f., 20) over time (in milliseconds), and FIG. 10Bdepicts the voltage (in volts) across the power bus capacitor (c.f., C1)over time (in milliseconds). As shown in FIGS. 10A and 10B with thesystem that does not use the exemplary charge management system, at 2milliseconds the FETs are deactivated to operably disconnect the load(shown at 510′), and at 2.09 milliseconds the voltage across the powerbus capacitor increases to 426Vdc (shown at 515′). In addition, thecurrent through the load goes to zero at approximately 2.6 milliseconds(shown at 520′), and the voltage across the power bus capacitor remainsat about 320Vdc (shown at 525′) as there is nowhere for the energy to bedistributed.

In comparison, FIGS. 11A and 11B illustrate a simulation using theexemplary charge management system 10, where FIG. 11A depicts current(in amperes) through the load 20 over time (in milliseconds), and FIG.11B depicts the voltage (in volts) across the power bus capacitor C1over time (in milliseconds). As shown in FIGS. 11A and 11B, at 2milliseconds the FETs are deactivated to operably disconnect the load(shown at 510″). The system controller 16 then determines that the loadhas been deactivated, and the energy storage charge switch S3 isdeactivated and the energy capture switch S5 is activated, therebyenabling energy in the power bus capacitor C1 to be discharged to the tothe energy capture capacitors C3 and C4, as discussed above. At about2.02 milliseconds, the voltage across the power bus capacitor C1 is312Vdc (shown at 515″), which is 114Vdc less than that shown in FIGS. 9Aand 9B. In addition, the current through the load 20 goes to zero atapproximately 2.6 milliseconds (shown at 520′″), and the voltage acrossthe power bus capacitor C1 remains at about 280Vdc (shown at 525″).

Turning to FIG. 12, an exemplary circuit diagram of a simulated chargemanagement system 610 is shown. In the illustrated embodiment of FIG.12, the same reference numerals are used to denote structures in thecharge management system 610 that correspond to the same or similarstructures in the charge management system 10. In addition, theforegoing description of the charge management system 10 is equallyapplicable to the charge management system 610, and it will beappreciated that aspects of the charge management systems 10, 610 may besubstituted for one another or used in conjunction with one anotherwhere applicable.

As shown in FIG. 12, the charge management system 610 includes a primarypower source V1, a primary power bus capacitor C1, and primary powerrelay switches S1 and S2 for operably coupling the primary power sourceV1 to a load 20, which in the simulated circuit 610 is shown as voltagesource V5, switch S6, and resistor R1. The charge management system 610also includes an energy source V2; at least one energy storage capacitorC5, which includes energy storage capacitors C2, C3, and C4; an energystorage capacitor charge switch S3; an energy storage capacitordischarge switch S4; and an energy capture charge switch S5.

The charge management system 610 also includes a system controller 16,which is shown as circuitry in the illustrated embodiment. The systemcontroller 16 includes a voltage source V3; an AND gate A2; resistorsR9, R10, R20, R2, R3, R4, R5, R23, R6, R8, R10, and R15; an operationalamplifier U1; inverters A6 and A4; and comparators U6, U5, and U8.

As described hereinabove, an exemplary charge management system includesa power distribution bus circuit for distributing energy from a powersource to a load, and an intermediate energy storage circuit operablyconnected to a power distribution bus circuit for aiding in distributionof energy to the load. A charge management system controller may beconfigured to control the discharge of energy between the intermediatestorage circuit and the power distribution bus circuit during one ormore modes. Such a charge management system may enable the powerdistribution bus circuit to receive energy from the intermediate energystorage circuit before the power bus voltage drops in response to loaddemand, which may enable the power source to respond to perturbations inthe power bus voltage and minimize inrush current from the power source.The system also may be used to soft-start high-power equipment, allowregenerative energy storage, and/or absorb energy spikes associated withshut-down of such high-power equipment, among other considerations.

According to one aspect of the invention, a method of operating a chargemanagement system for distributing power from a power source to a load,the charge management system including a power distribution bus circuitoperably connected to the power source and the load, and an intermediateenergy storage circuit operably connected to the power distribution buscircuit, the method including: (i) charging at least one energy storagecapacitor in the intermediate energy storage circuit; (ii) activating adischarge switch to operably connect the at least one energy storagecapacitor to at least one power bus capacitor in the power distributionbus circuit, thereby discharging at least some energy stored in theenergy storage capacitor to the at least one power bus capacitor; (iii)deactivating the discharge switch to operably disconnect the at leastone energy storage capacitor from the at least one power bus capacitor;and (iv) determining whether voltage across the at least one power buscapacitor is within a predetermined range; wherein, when voltage acrossthe at least one power bus capacitor is not within the predeterminedrange during the determining, then repeating steps (i) through (iv); andwherein, when voltage across the at least one power bus capacitor iswithin the predetermined range during the determining, then operablyconnecting the power source to the load.

Embodiments of the invention may include one or more of the followingadditional features separately or in combination.

The deactivating the discharge switch may be based upon a determinationthat the at least one energy storage capacitor and the at least onepower bus capacitor are within a predetermined range.

The at least one energy storage capacitor may be charged by activatingan energy storage capacitor charge switch to operably connect the atleast one energy storage capacitor to at least one energy source.

The at least one energy source may be different from the power source.

The charging the at least one energy storage capacitor may includecharging to a predetermined level.

After charging the at least one energy storage capacitor to thepredetermined level, the method may further include deactivating theenergy storage capacitor charge switch to operably disconnect the atleast one energy storage capacitor from the at least one energy source.

According to another aspect of the invention, a method of operating acharge management system for distributing power from a power source to aload, the charge management system including a power distribution buscircuit operably connected to the power source and the load, and anintermediate energy storage circuit operably connected to the powerdistribution bus circuit, the method including: (i) operably connectingthe power source to the load; (ii) charging at least one energy storagecapacitor in the intermediate energy storage circuit; (iii) determiningload current demand, and based upon a determination that the loaddemands current that meets or exceeds a predetermined level, activatinga discharge switch to operably connect the at least one energy storagecapacitor in the intermediate energy storage circuit to at least onepower bus capacitor in the power distribution bus circuit, therebydischarging at least some energy stored in the energy storage capacitorand at least some energy stored in the power bus capacitor to the load;(iv) deactivating the discharge switch to operably disconnect the atleast one energy storage capacitor from the at least one power buscapacitor; and (v) repeating steps (ii) through (iv).

Embodiments of the invention may include one or more of the followingadditional features separately or in combination.

The deactivating the discharge switch may be based upon a determinationthat the at least one energy storage capacitor and the at least onepower bus capacitor are within a predetermined range.

The at least one energy storage capacitor may be charged by activatingan energy storage capacitor charge switch to operably connect the atleast one energy storage capacitor to at least one energy source.

The at least one energy source may be different than the power source.

During the charging the at least one energy storage capacitor, themethod may further include determining when the voltage across the atleast one energy storage capacitor is within a predetermined range.

The activating the discharge switch to operably connect the at least oneenergy storage capacitor to the at least one power bus capacitor may bebased upon a determination that the voltage across the at least oneenergy storage capacitor is within the predetermined range.

The at least one energy storage capacitor may include a first energystorage capacitor, a second energy storage capacitor, and a third energystorage capacitor.

The second and third energy storage capacitors may be operably connectedin series with each other.

The first energy storage capacitor may be operably connected in parallelwith the second and third energy storage capacitors.

When the discharge switch is activated, energy stored in the respectivefirst, second, and third energy storage capacitors may beinstantaneously discharged to the load, thereby causing an increase inoutput voltage, current applied to the load, and current the beingsourced by the primary power source.

The method may further include determining voltage across the at leastone power bus capacitor in the power distribution bus circuit, and basedupon a determination that the voltage across the at least one power buscapacitor is greater than a predetermined level, activating a capturecharge switch to operably connect the at least one power bus capacitorto the at least one energy storage capacitor, thereby discharging atleast some energy stored in the at least one power bus capacitor to theat least one energy capture capacitor.

The at least one energy storage capacitor may include a first energystorage capacitor and a second energy storage capacitor in series witheach other, the respective first and second energy storage capacitorsbeing configured to capture the energy discharged from the at least onepower bus capacitor when the capture charge switch is activated.

The method may further include deactivating the capture charge switch tooperably disconnect the at least one power bus capacitor from the atleast one energy storage capacitor.

The deactivating the capture charge switch may be based upon adetermination that the at least one energy storage capacitor and the atleast one power bus capacitor are within a predetermined range.

The method may further include determining when a shutdown commandsignal has been received, and based upon a determination that theshutdown command signal has been received, deactivating the energystorage capacitor charge switch, and activating the discharge switch,thereby discharging the at least one energy storage capacitor and the atleast one power bus capacitor.

According to another aspect of the invention, a method of operating acharge management system for distributing power from a power source to aload, the charge management system including a power distribution buscircuit operably connected to the power source and the load, and anintermediate energy storage circuit operably connected to the powerdistribution bus circuit, the method including: (i) determining voltageacross at least one a power bus capacitor in the power distribution buscircuit, and based upon a determination that the voltage across the atleast one power bus capacitor is greater than a predetermined level,activating a capture charge switch to operably connect the at least onepower bus capacitor to at least one energy storage capacitor in theintermediate energy storage circuit, thereby discharging at least someenergy stored in the at least one power bus capacitor to the at leastone energy storage capacitor; (ii) deactivating the capture chargeswitch to operably disconnect the at least one power bus capacitor fromthe at least one energy storage capacitor; (iii) further charging the atleast one energy storage capacitor in the intermediate energy storagecircuit based upon a determination that the voltage across the at leastone energy storage capacitor is below a predetermined level; (iii)determining load current demand, and based upon a determination that theload demands current that meets or exceeds a predetermined level,activating a discharge switch to operably connect the at least oneenergy storage capacitor to the at least one power bus capacitor,thereby discharging at least some energy stored in the energy storagecapacitor and at least some energy stored in the power bus capacitor tothe load; and (iv) deactivating the discharge switch to operablydisconnect the at least one energy storage capacitor from the at leastone power bus capacitor.

Embodiments of the invention may include one or more of the followingadditional features separately or in combination.

The at least one energy storage capacitor in the intermediate energystorage circuit may include a first energy storage capacitor, a secondenergy storage capacitor, and a third energy storage capacitor.

The second and third energy storage capacitors may be operably connectedin series with each other, and the first energy storage capacitor may beoperably connected in parallel with the second and third energy storagecapacitors.

When the capture charge switch is activated to operably connect the atleast one power bus capacitor to the at least one energy storagecapacitor, at least some energy stored in the at least one power buscapacitor may be discharged to the second and third energy storagecapacitors.

The further charging the at least one energy storage capacitor mayinclude activating an energy storage capacitor charge switch to operablyconnect the first energy storage capacitor to at least one energy sourcethat is different from the power source.

When the discharge switch is activated, energy stored in the respectivefirst, second, and third energy storage capacitors and energy stored inthe at least one power bus capacitor may be discharged to the load.

According to another aspect of the invention, a charge management systemfor distributing power from a power source to a load via a powerdistribution bus circuit having at least one power bus capacitor, thecharge management system includes: an intermediate energy storagecircuit operably connected to the power distribution bus circuit, theintermediate energy storage circuit having at least one energy storagecapacitor, and at least one discharge switch configured to operablyconnect or disconnect the at least one energy storage capacitor to orfrom the at least one power bus capacitor; and a system controlleroperably connected to the power bus distribution circuit and theintermediate energy storage circuit.

Embodiments of the invention may include one or more of the followingadditional features separately or in combination.

For example, the system controller may be configured to carry out one ormore of the aforementioned method steps.

For example, in a start-up mode, the system controller may be configuredto: (i) activate an energy storage capacitor charge switch to operablyconnect the at least one energy storage capacitor to at least one energysource, thereby enabling charging of the at least one energy storagecapacitor; (ii) activate a discharge switch to operably connect the atleast one energy storage capacitor to the at least one power buscapacitor, thereby enabling discharging of at least some energy storedin the energy storage capacitor to the at least one power bus capacitor;(iii) deactivate the discharge switch to operably disconnect the atleast one energy storage capacitor from the at least one power buscapacitor; and (iv) determine whether the voltage across the at leastone power bus capacitor is within a predetermined range, such that,based upon a determination that the voltage across the at least onepower bus capacitor is not within the predetermined range, thecontroller is configured to repeat steps (i) through (iv), and basedupon a determination that the voltage across the at least one power buscapacitor is within the predetermined range during the determining, thecontroller is configured to activate a power relay switch to operablyconnect the power source to the load.

In an operational mode, the system controller may be configured to: (i)operably connect the power source to the load; (ii) determine whetherthe voltage across the at least one energy storage capacitor is at orabove a predetermined level, and based upon a determination that thevoltage across the energy storage capacitor is below the predeterminedlevel, the controller is configured to activate the energy storagecapacitor charge switch to operably connect the at least one energystorage capacitor to the at least one energy source, thereby enablingcharging of the at least one energy storage capacitor; (iii) determineload current demand, and based upon a determination that the loaddemands current that meets or exceeds a predetermined level, activatingthe discharge switch to operably connect the at least one energy storagecapacitor to the at least one power bus capacitor, thereby enablingdischarging of at least some energy stored in the energy storagecapacitor and at least some energy stored in the power bus capacitor tothe load; and (iv) deactivating the discharge switch to operablydisconnect the at least one energy storage capacitor from the at leastone power bus capacitor.

In a regenerative mode, the controller may be configured to determinevoltage across the at least one a power bus capacitor, and based upon adetermination that the voltage across the at least one power buscapacitor is greater than a predetermined level, the controller isconfigured to activate a capture charge switch to operably connect theat least one power bus capacitor to the at least one energy storagecapacitor, thereby enabling discharging of at least some energy storedin the at least one power bus capacitor to the at least one energystorage capacitor.

The at least one energy storage capacitor may include a first energystorage capacitor, a second energy storage capacitor, and a third energystorage capacitor.

The second and third energy storage capacitors may be operably connectedin series with each other across the intermediate energy storagecircuit, and the first energy storage capacitor may be operablyconnected in parallel with the second and third energy storagecapacitors.

In the operational mode, the controller may be configured to activatethe energy storage capacitor charge switch to operably connect the firstenergy storage capacitor to the at least one energy source, therebyenabling charging of the first energy storage capacitor.

In the regenerative mode, the controller may be configured to activatethe capture charge switch to operably connect the at least one power buscapacitor to the second and third capacitors, thereby enabling at leastsome energy stored in the at least one power bus capacitor to bedischarged to the second and third energy storage capacitors.

The controller may be configured to activate the discharge switch,thereby enabling energy stored in the respective first, second, andthird energy storage capacitors and energy stored in the at least onepower bus capacitor to be discharged to the load.

In the exemplary flow diagrams of FIGS. 2, 5, 7 and 9 described above,blocks denote “processing blocks” that may be implemented with logic.The processing blocks may represent a method step or an apparatuselement for performing the method step. A flow diagram does not depictsyntax for any particular programming language, methodology, or style(e.g., procedural, object-oriented). Rather, a flow diagram illustratesfunctional information one skilled in the art may employ to developlogic to perform the illustrated processing. It will be appreciated thatin some examples, program elements like temporary variables, routineloops, and so on, are not shown. It will be further appreciated thatelectronic and software applications may involve dynamic and flexibleprocesses so that the illustrated blocks can be performed in othersequences that are different from those shown or that blocks may becombined or separated into multiple components. It will be appreciatedthat the processes may be implemented using various programmingapproaches like machine language, procedural, object oriented orartificial intelligence techniques. In exemplary embodiments,methodologies are implemented as processor executable instructions oroperations provided by a controller or on a computer-readable medium.Thus, in one example, a computer-readable medium may store processorexecutable instructions operable to perform a method. It is furtherunderstood that while FIGS. 2, 5, 7 and 8 illustrate various actionsoccurring in serial, it is to be appreciated that various actionsillustrated in these embodiments could occur substantially in parallel.

Algorithmic descriptions and representations used herein are the meansused by those skilled in the art to convey the substance of their workto others. An algorithm or method is here, and generally, conceived tobe a sequence of operations that produce a result. The operations mayinclude physical manipulations of physical quantities. Usually, thoughnot necessarily, the physical quantities take the form of electrical ormagnetic signals capable of being stored, transferred, combined,compared, and otherwise manipulated in a logic and the like.

It has proven convenient at times, principally for reasons of commonusage, to refer to these signals as bits, values, elements, symbols,characters, terms, numbers, or the like. It should be borne in mind,however, that these and similar terms are to be associated with theappropriate physical quantities and are merely convenient labels appliedto these quantities. Unless specifically stated otherwise, it isappreciated that throughout the description, terms like processing,computing, calculating, determining, displaying, or the like, refer toactions and processes of a computer system, logic, processor, or similarelectronic device that manipulates and transforms data represented asphysical (electronic) quantities.

To the extent that the term “includes” or “including” is employed in thedetailed description or the claims, it is intended to be inclusive in amanner similar to the term “comprising” as that term is interpreted whenemployed as a transitional word in a claim. Furthermore, to the extentthat the term “or” is employed in the detailed description or claims(e.g., A or B) it is intended to mean “A or B or both.” When theapplicants intend to indicate “only A or B but not both” then the term“only A or B but not both” will be employed. Thus, use of the term “or”herein is the inclusive, and not the exclusive use.

An “operable connection,” as used herein, or a connection by whichentities are “operably connected” or are “operably coupled,” is one inwhich signals, physical communications, or logical communications may besent or received. Typically, an operable connection includes a physicalinterface, an electrical interface, or a data interface, but it is to benoted that an operable connection may include differing combinations ofthese or other types of connections sufficient to allow operablecontrol. For example, two entities can be operably connected by beingable to communicate signals to each other directly or through one ormore intermediate entities like a processor, operating system, a logic,software, or other entity. Logical or physical communication channelscan be used to create an operable connection.

“Logic,” as used herein, includes but is not limited to hardware,firmware, software or combinations of each to perform a function(s) oran action(s), or to cause a function or action from another logic,method, or system. For example, based on a desired application or needs,logic may include a software controlled microprocessor, discrete logiclike an application specific integrated circuit (ASIC), a programmedlogic device, a memory device containing instructions, or the like.Logic may include one or more gates, combinations of gates, or othercircuit components. Logic may also be fully embodied as software. Wheremultiple logical logics are described, it may be possible to incorporatethe multiple logical logics into one physical logic. Similarly, where asingle logical logic is described, it may be possible to distribute thatsingle logical logic between multiple physical logics.

“Computer program,” as used herein, (also known as a program, software,software application, script, or code) can be written in any form ofprogramming language, including compiled or interpreted languages,declarative or procedural languages, and it can be deployed in any form,including as a stand-alone program or as a module, component,subroutine, or other unit suitable for use in a computing environment. Acomputer program does not necessarily correspond to a file in a filesystem. A program can be stored in a portion of a file that holds otherprograms or data (e.g., one or more scripts stored in a markup languagedocument), in a single file dedicated to the program in question, or inmultiple coordinated files (e.g., files that store one or more modules,sub-programs, or portions of code). A computer program can be deployedto be executed on one computer or on multiple computers that are locatedat one site or distributed across multiple sites and interconnected by acommunication network.

“Software,” as used herein, includes but is not limited to, one or morecomputer or processor instructions that can be read, interpreted,compiled, or executed and that cause a computer, processor, or otherelectronic device to perform functions, actions or behave in a desiredmanner. The instructions may be embodied in various forms like routines,algorithms, modules, methods, threads, or programs including separateapplications or code from dynamically or statically linked libraries.Software may also be implemented in a variety of executable or loadableforms including, but not limited to, a stand-alone program, a functioncall (local or remote), a servlet, an applet, instructions stored in amemory, part of an operating system or other types of executableinstructions. It will be appreciated by one of ordinary skill in the artthat the form of software may depend, for example, on requirements of adesired application, the environment in which it runs, or the desires ofa designer/programmer or the like. It will also be appreciated thatcomputer-readable or executable instructions can be located in one logicor distributed between two or more communicating, co-operating, orparallel processing logics and thus can be loaded or executed in serial,parallel, massively parallel and other manners. Software, whether anentire system or a component of a system, may be embodied as an articleof manufacture and maintained or provided as part of a computer-readablemedium.

It is understood that embodiments of the subject matter described inthis specification can be implemented in combination with digitalelectronic circuitry, or computer software, firmware, or hardware.Embodiments of the subject matter described in this specification can beimplemented in a charge management system that uses one or more modulesof computer program instructions encoded on a computer-readable mediumfor execution by, or to control the operation of, data processingapparatus. The computer-readable medium can be a manufactured product,such as hard drive in a computer system or an optical disc sold throughretail channels, or an embedded system. The computer-readable medium canbe acquired separately and later encoded with the one or more modules ofcomputer program instructions, such as by delivery of the one or moremodules of computer program instructions over a wired or wirelessnetwork. The computer-readable medium can be a machine-readable storagedevice, a machine-readable storage substrate, a memory device, or acombination of one or more of them.

As discussed above, the system controller 16 encompasses all apparatus,devices, and machines for processing data, including by way of example aprogrammable processor, a computer, or multiple processors or computers.The apparatus can include, in addition to hardware, code that creates anexecution environment for the computer program in question, e.g., codethat constitutes processor firmware, a protocol stack, a databasemanagement system, an operating system, a runtime environment, or acombination of one or more of them. In addition, the apparatus canemploy various different computing model infrastructures, such as webservices, distributed computing and grid computing infrastructures.

Processors encompass all apparatus, devices, and machines suitable forthe execution of a computer program include, by way of example, bothgeneral and special purpose microprocessors, and any one or moreprocessors of any kind of digital computer. Generally, a processor willreceive instructions and data from a read-only memory or a random accessmemory or both. The essential elements of a computer include a processorfor performing instructions and one or more memory devices for storinginstructions and data. Generally, a computer will also include, or beoperably coupled to receive data from or transfer data to, or both, oneor more mass storage devices for storing data, e.g., magnetic,magneto-optical disks, or optical disks. However, a computer need nothave such devices. Moreover, a computer can be embedded in anotherdevice, e.g., a mobile device or portable storage device (e.g., auniversal serial bus (USB) flash drive. Devices suitable for storingcomputer program instructions and data include all forms of non-volatilememory, media and memory devices, including by way of examplesemiconductor memory devices, e.g., EPROM, EEPROM, and flash memorydevices; magnetic disks, e.g., internal hard disks or removable disks;magneto-optical disks; and CD-ROM and DVD-ROM disks. The processor andthe memory can be supplemented by, or incorporated in, special purposelogic circuitry.

Although the invention has been shown and described with respect to acertain embodiment or embodiments, it is obvious that equivalentalterations and modifications will occur to others skilled in the artupon the reading and understanding of this specification and the annexeddrawings. In particular regard to the various functions performed by theabove described elements (components, assemblies, devices, compositions,etc.), the terms (including a reference to a “means”) used to describesuch elements are intended to correspond, unless otherwise indicated, toany element which performs the specified function of the describedelement (i.e., that is functionally equivalent), even though notstructurally equivalent to the disclosed structure which performs thefunction in the herein illustrated exemplary embodiment or embodimentsof the invention. In addition, while a particular feature of theinvention may have been described above with respect to only one or moreof several illustrated embodiments, such feature may be combined withone or more other features of the other embodiments, as may be desiredand advantageous for any given or particular application.

What is claimed is:
 1. A method of operating a charge management systemfor distributing power from a power source to a load, the chargemanagement system including a power distribution bus circuit operablyconnected to the power source and the load, and an intermediate energystorage circuit operably connected to the power distribution buscircuit, the method comprising: (i) determining voltage across at leastone a power bus capacitor in the power distribution bus circuit, andbased upon a determination that the voltage across the at least onepower bus capacitor is greater than a predetermined level, activating acapture charge switch to operably connect the at least one power buscapacitor to at least one energy storage capacitor in the intermediateenergy storage circuit, thereby discharging at least some energy storedin the at least one power bus capacitor to the at least one energystorage capacitor; (ii) deactivating the capture charge switch tooperably disconnect the at least one power bus capacitor from the atleast one energy storage capacitor; and (iii) determining load currentdemand, and based upon a determination that the load demands currentthat meets or exceeds a predetermined level, activating a dischargeswitch to operably connect the at least one energy storage capacitor tothe at least one power bus capacitor, thereby discharging at least someenergy stored in the energy storage capacitor and at least some energystored in the power bus capacitor to the load.
 2. The method accordingto claim 1, wherein after step (iii), the method further comprises: (iv)deactivating the discharge switch to operably disconnect the at leastone energy storage capacitor from the at least one power bus capacitor.3. The method according to claim 1, wherein between step (ii) and step(iii) the method further comprises: further charging the at least oneenergy storage capacitor in the intermediate energy storage circuitbased upon a determination that the voltage across the at least oneenergy storage capacitor is below a predetermined level.
 4. The methodaccording to claim 3, wherein the further charging the at least oneenergy storage capacitor includes activating an energy storage capacitorcharge switch to operably connect the at least one energy storagecapacitor to an energy source.
 5. The method according to claim 4,wherein the power distribution bus circuit is operably connected to apower source, and wherein the power source is operably connected to theload across the power distribution bus circuit by activating a powerrelay switch, in which activation of the power relay switch alsooperably connects the at least one power bus capacitor to the powersource.
 6. The method according to claim 5, wherein the energy source isdifferent from the power source.
 7. The method according to claim 5,wherein the energy storage capacitor charge switch and the power relayswitch are operable independently of each other.
 8. The method accordingto claim 7, wherein the energy source is operably coupled to the powersource to receive energy from the power source.
 9. The method accordingto claim 4, wherein after step (i) and before step (ii), the methodfurther comprising deactivating the energy storage capacitor chargeswitch to operably disconnect the at least one energy storage capacitorfrom energy source.
 10. The method according to claim 1, wherein atleast steps (i) through (iii) are carried out while the load is appliedacross the power distribution bus circuit.
 11. The method according toclaim 1, wherein the at least one energy storage capacitor in theintermediate energy storage circuit includes a first energy storagecapacitor, a second energy storage capacitor, and a third energy storagecapacitor, the second and third energy storage capacitors being operablyconnected in series with each other, and the first energy storagecapacitor being operably connected in parallel with the second and thirdenergy storage capacitors.
 12. The method according to claim 11,wherein, when the capture charge switch is activated to operably connectthe at least one power bus capacitor to the at least one energy storagecapacitor, at least some energy stored in the at least one power buscapacitor is discharged to the second and third energy storagecapacitors.
 13. The method according to claim 12, wherein the methodfurther comprises: further charging the at least one energy storagecapacitor in the intermediate energy storage circuit based upon adetermination that the voltage across the at least one energy storagecapacitor is below a predetermined level; and wherein, the furthercharging the at least one energy storage capacitor includes activatingan energy storage capacitor charge switch to operably connect the firstenergy storage capacitor to at least one energy source that is differentfrom the power source.
 14. The method according to claim 13, wherein,when the discharge switch is activated, energy stored in the respectivefirst, second, and third energy storage capacitors and energy stored inthe at least one power bus capacitor is discharged to the load.
 15. Acharge management system for distributing power from a power source to aload via a power distribution bus circuit having at least one power buscapacitor, the charge management system comprising: an intermediateenergy storage circuit operably connected to the power distribution buscircuit, the intermediate energy storage circuit having at least oneenergy storage capacitor, and at least one discharge switch configuredto operably connect or disconnect the at least one energy storagecapacitor to or from the at least one power bus capacitor; and a systemcontroller operably connected to the power bus distribution circuit andthe intermediate energy storage circuit; wherein the system controlleris configured to: (i) determine voltage across at least one a power buscapacitor in the power distribution bus circuit, and based upon adetermination that the voltage across the at least one power buscapacitor is greater than a predetermined level, activate a capturecharge switch to operably connect the at least one power bus capacitorto at least one energy storage capacitor in the intermediate energystorage circuit, thereby discharging at least some energy stored in theat least one power bus capacitor to the at least one energy storagecapacitor; (ii) deactivate the capture charge switch to operablydisconnect the at least one power bus capacitor from the at least oneenergy storage capacitor; (iii) determine load current demand, and basedupon a determination that the load demands current that meets or exceedsa predetermined level, activate a discharge switch to operably connectthe at least one energy storage capacitor to the at least one power buscapacitor, thereby discharging at least some energy stored in the energystorage capacitor and at least some energy stored in the power buscapacitor to the load.
 16. The charge management system according toclaim 15, wherein: between step (ii) and step (iii) the systemcontroller is configured to: further charge the at least one energystorage capacitor in the intermediate energy storage circuit based upona determination that the voltage across the at least one energy storagecapacitor is below a predetermined level; and/or after step (iii), thesystem controller is configured to: (iv) deactivate the discharge switchto operably disconnect the at least one energy storage capacitor fromthe at least one power bus capacitor.
 17. The charge management systemaccording to claim 16, wherein the further charging the at least oneenergy storage capacitor includes activating an energy storage capacitorcharge switch to operably connect the at least one energy storagecapacitor to an energy source.
 18. The charge management systemaccording to claim 15, wherein the at least one energy storage capacitorincludes a first energy storage capacitor, a second energy storagecapacitor, and a third energy storage capacitor, the second and thirdenergy storage capacitors being operably connected in series with eachother across the intermediate energy storage circuit, and the firstenergy storage capacitor being operably connected in parallel with thesecond and third energy storage capacitors.
 19. The charge managementsystem according to claim 18, wherein the system controller isconfigured to activate the capture charge switch to operably connect theat least one power bus capacitor to the second and third capacitors,thereby enabling at least some energy stored in the at least one powerbus capacitor to be discharged to the second and third energy storagecapacitors.
 20. The charge management system according to claim 19,wherein the controller is configured to activate the discharge switch,thereby enabling energy stored in the respective first, second, andthird energy storage capacitors and energy stored in the at least onepower bus capacitor to be discharged to the load.